The present invention relates to spraying devices, and particularly to the type of spraying devices described in my Israel Patent 61186 (U.S. Pat. No. 4,356,974), as well as in my Israel Patents 45916 (U.S. Pat. No. 3,958,760), and 78235 (U.S. Pat. No. 4,760,957).
Spraying devices of the foregoing type are used as mini-sprinklers in water irrigation systems. Such mini-sprinklers generally comprise a nozzle head formed with an axial bore therethrough having an inlet end connectible to a source of pressurized liquid, an outlet end defining an outlet orifice through which the liquid exits in the form of a jet, and a connecting passageway connecting the inlet end to the outlet orifice; a rod passing through the axial bore; and a liquid distribution member secured to the rod at the outlet orifice end thereof to distribute the liquid laterally of the nozzle head. The rod is of smaller transverse dimension and of longer length than the axial bore and carries an abutment at the bore inlet end thereof such that the rod is displaceable both axially and laterally within the axial bore.
The output rate of such mini-sprinklers is determined by the cross-section of the flow passage defined by the space between the rod and the surface of the axial bore. Different applications of such mini-sprinklers require different flow rates, and therefore such mini-sprinklers are supplied in a range of different flow rates according to the dimensions of the rod and the axial bore.